1. Field of the Invention
The present invention relates to a washing machine with a functional water generator and a washing method thereof, and more particularly, to a washing machine having improved cleaning efficiency by adding a generator of functional water such as ozone water or electrolyzed water to a full-automatic washing machine, and a washing method thereof.
2. Description of the Related Art
Currently, full-automatic washing machines in which laundry washing, rinsing and dewatering are sequentially performed, are widely used. Also, there have been developed a washing machine with a filtering system for increasing cleaning efficiency and a washing machine with an ozone generator for sterilizing, disinfecting or bleaching the laundry.
An example of the washing machine with an ozone generator is disclosed in Korean Patent Publication No. 1996-14275. FIG. 1 illustrates a conventional washing machine in which ozone gas is generated in the air and then the generated ozone gas is dissolved into water. Referring to FIG. 1, the conventional washing machine includes first and second water supply valves 81 and 82 installed in a body to be selectively opened or closed for supplying hot water or cold water to a tub 80, a filter 85 for filtering washing water introduced through the first and second water supply valves 81 and 82 and first and second solenoid valves 83 and 84, an ozone gas generator 87 for generating ozone gas by driving an air pump 86, a sprinkler 88 for introducing the ozone gas generated by the ozone gas generator 87 into the tub 80, and a catalyst filter 89 for removing undissolved ozone gas introduced into the tub 80.
In the aforementioned washing machine, when the level of washing water in the tub 80 comes to a predetermined level after beginning water supply, ozone gas is generated from the ozone gas generator 87 by driving the air pump 86 disposed under the tub 80. The generated ozone gas is introduced into the tub 80 through a plurality of holes each having a diameter of 10 xcexcm or less of the sparkler 88 which is made of ceramic and installed at one side of a pulsator on the bottom of the tub 80, and at the same time the washing water in the tub 80 is agitated by rotation of the pulsator, thereby dissolving the ozone gas. The undissolved ozone gas moves upward in the tub 80 to be removed by the catalyst filter 89 which is installed in the upper portion of the tub 80 out of contact with the washing water.
However, an ozone gas requires a considerable time to be dissolved in water, and the time is dependent upon the shape and size of the ozone gas when it is brought into contact with water. In particular, ozone gas particles with small size are advantageously dissolved in water. Thus, in a washing machine based on a method in which ozone gas is generated in the air and then dissolved in water, a separate device is required for making ozone gas into fine particles. Further, the undissolved ozone gas emanated into the air would be harmful to the user. Thus, it is necessary to remove the harmful ozone gas using a separate device, which increases financial burden of equipment. Also, the user""s safety cannot be ensured due to the emanated ozone gas. As described above, the conventional washing machine with an ozone gas generator worked in the air has many problems.
Alternative washing machine with an ozone generator is disclosed in Korean Patent Publication No.1992-7734, in which ozone is generated by hydrolysis of water and the obtained ozone water is supplied for washing. FIG. 2 illustrates a conventional washing machine in which ozone is generated in water. The washing machine, which is configured to sequentially perform washing, rinsing and dewatering, includes a water supply valve 91 for automatically supplying or blocking tap water and a water supply tube 92 for introducing the water into a washing tub. An ozone generator 93 is provided between the water supply valve 91 and the water supply tube 92 so as to generate ozone water simultaneously with supplying of water for a final rinsing step. The ozone generator 93 having an inlet conduit in its upper portion, an outlet conduit it its lower portion, and upper and lower cases tightened by threads is connected to a water supply tube of the washing tub, thereby directly supplying ozone water into the washing machine simultaneously with water supply.
However, according to the above-described washing machine with an ozone generator installed on a water supply tube for generating ozone in water, the ozone water is directly supplied to the laundry, resulting in decolorization or damage of the laundry. Also, since the action of oxidizing power starts with the supply of the ozone water, the duration of the reaction time is short. Further, the concentration of the ozone water is undesirably variable due to the flux of supplied water.
To solve the problems encountered in the conventional washing machine with an ozone generator, it is an object of the present invention to provide a washing machine having improved cleaning efficiency, which is additionally installed with a simple device for generating functional water in washing water supplied to a washing tub in a full-automatic washing machine, to generate functional water such as ozone water or electrolyzed water. The functional water is consistently act on the laundry in a constant concentration, which prevents partial decolorization or damage of the laundry and simultaneously perform sterilization, disinfection and bleaching of the laundry, thereby improving a degree of cleaning while reducing the use amount of detergent.
To accomplish the above object of the present invention, there is provided a washing machine including a water supplier for supplying washing water, a washing tub for containing the washing water supplied from the water supplier and a laundry, a functional water generator installed inside the washing tub, and an agitator for agitating the washing water and the laundry contained in the washing tub.
The functional water generator, which generates functional water in the washing water supplied to the washing tub, is preferably provided in the lower portion of the washing tub. Particularly, the functional water generator may be an ozone water generator having at least one pair of facing electrodes or an electrolyzed water generator having at least one pair of facing electrodes disposed with a separating layer interposed therebetween. The facing electrodes are preferably made of platinum (Pt), a platinum/palladium (Pt/Pd) alloy or a Pt group/Pd alloy. Further, the facing electrodes may be made of a conductive metal coated with platinum (Pt), a platinum/palladium (Pt/Pd) alloy or a Pt group/Pd alloy. The conductive metal is preferably titanium (Ti). In the case of using the Pt/Pd alloy, 85.0 to 99.95 wt % of Pt and 15.0 to 0.05 wt % of Pd are preferably contained in the alloy. Also, the facing electrodes are preferably carbon electrodes having electric conductivity.
The facing electrodes may be of a panel type, a flat panel type having one or more holes, a small strip type, a fine wire type, a fish bone type, a mesh type or a cylinder type. The distance of the facing electrodes is preferably in the range of 0.1 to 1 mm.
Also, the washing machine may further include a power source for applying a direct-current (DC) voltage, a pulse voltage, a square wave pulse voltage, a sequence-controlled pulse voltage or an alternating pulse voltage to the functional water generator.
The washing machine may further include a power source for applying a voltage to the functional water generator, a sensor for sensing whether the washing water supplied from the water supplier reaches a predetermined level in the washing tub, and a controller for receiving information of the level of the washing water in the washing tub from the sensor and controlling the voltage to be applied to the power source. Also, the washing machine may further include a power source for applying a voltage to the functional water generator, a sensor for sensing the concentration of the functional water in the washing tub, and a controller for receiving information of the concentration of the functional water from the sensor and controlling the voltage to be applied to the power source. Here, the controller may further controls the operations of a water supply valve for supplying the washing water to the washing tub and a drain valve for draining the washing water from the washing tub.
There is further provided a washing machine including means for supplying washing water to a washing tub, means for generating functional water in the washing water supplied to the washing tub, means for mixing a laundry with the functional water, and means for draining the functional water.
The functional water is ozone water or electrolyzed water, and the electrolyzed water is acid water, alkali water or neutral water.
According to another aspect of the present invention, there is provided a washing method performed by a washing machine, including the steps of supplying washing water to a washing tub, generating functional water in the washing water supplied to the washing tub, mixing a laundry with the functional water, and draining the functional water.
The washing method may further include the steps of sensing the level of the washing water supplied to the washing tub, and controlling the generation of the functional water in accordance with the level of the washing water. Also, the washing machine may further including the steps of sensing the concentration of the functional water in the washing tub, and controlling the generation of the functional water in accordance with the concentration of the washing water.
In the present invention, the functional water generator for generating functional water having various functions of sterilization, disinfection, bleaching or deodorization, is installed in the washing tub of the washing machine. The functional water is generated after the washing water is supplied to the washing tub. According to the present invention, the functional water generator includes at least one pair of facing electrodes so that when a voltage is applied to the electrodes, the functional water is generated while the water supplied to the washing tub is electrolyzed. The functional water generator is positioned in the lower portion of the washing tub, preferably under the agitator. When the washing water supplied from the water supplier reaches a predetermined level in the washing tub, the generation of the functional water begins, and the agitator also starts operating, therefore, the concentration of ozone or electrolyte in the water is maintained at a constant level for a long time in the washing machine according to the present invention. While the conventional washing machine with an ozone generator connected to a water supply pipe causes partial decolorization and damage of the laundry due to non-uniformity of the ozone concentration in the washing water, the washing machine according to the present invention performs a sterilization, disinfection, bleaching and deodorization of the laundry without such decolorization and damage. Therefore, the cleaning degree can be improved while reducing the amount of detergent used, thereby improving the cleaning efficiency.